The first two blastomeres contribute unequally to the human embryo.

Retrospective lineage reconstruction of humans predicts that dramatic clonal imbalances in the body can be traced to the 2-cell stage embryo. However, whether and how such clonal asymmetries arise in the embryo is unclear. Here, we performed prospective lineage tracing of human embryos using live imaging, non-invasive cell labeling, and computational predictions to determine the contribution of each 2-cell stage blastomere to the epiblast (body), hypoblast (yolk sac), and trophectoderm (placenta). We show that the majority of epiblast cells originate from only one blastomere of the 2-cell stage embryo. We observe that only one to three cells become internalized at the 8-to-16-cell stage transition. Moreover, these internalized cells are more frequently derived from the first cell to divide at the 2-cell stage. We propose that cell division dynamics and a cell internalization bottleneck in the early embryo establish asymmetry in the clonal composition of the future human body.

Assessment of obstetric characteristics and outcomes associated with pregnancy with Turner syndrome.

OBJECTIVE: To assess national-level trends, characteristics, and outcomes of pregnancies with Turner syndrome in the United States. DESIGN: Cross-sectional study. SETTING: The Healthcare Cost and Utilization Project's National Inpatient Sample. SUBJECTS: A total of 17,865,495 hospital deliveries from 2016-2020. EXPOSURE: A diagnosis of Turner syndrome, identified according to the World Health Organization's International Classification of Disease 10th revision code of Q96. MAIN OUTCOME MEASURES: Obstetrics outcomes related to Turner syndrome, assessed with inverse probability of treatment weighting cohort and multivariable binary logistic regression modeling. RESULTS: The prevalence of pregnant patients with Turner syndrome was 7.0 per 100,000 deliveries (one in 14,235). The number of hospital deliveries with patients who have a diagnosis of Turner syndrome increased from 5.0 to 11.7 per 100,000 deliveries during the study period (adjusted-odds ratio [aOR] for 2020 vs. 2016; 2.18, 95% confidence interval [CI] 1.83-2.60). Pregnant patients with Turner syndrome were more likely to have a diagnosis of pregestational hypertension (4.8% vs. 2.8%; aOR 1.65; 95% CI 1.26-2.15), uterine anomaly (1.6% vs. 0.4%; aOR, 3.01; 95% CI 1.93-4.69), and prior pregnancy losses (1.6% vs. 0.3%; aOR 4.70; 95% CI 3.01-7.32) compared with those without Turner syndrome. For the index obstetric characteristics, Turner syndrome was associated with an increased risk of intrauterine fetal demise (10.9% vs. 0.7%; aOR 8.40; 95% CI 5.30-13.30), intrauterine growth restriction (8.5% vs. 3.5%; aOR 2.11; 95% CI 1.48-2.99), and placenta accreta spectrum (aOR 3.63; 95% CI 1.20-10.97). For delivery outcome, pregnant patients with Turner syndrome were more likely to undergo cesarean delivery (41.6% vs. 32.3%; aOR 1.53; 95% CI 1.26-1.87). Moreover, the odds of periviable delivery (22-25 weeks: 6.1% vs. 0.4%; aOR 5.88; 95% CI 3.47-9.98) and previable delivery (<22 weeks: 3.3% vs. 0.3%; aOR 2.87; 95% CI 1.45-5.69) were increased compared with those without Turner syndrome. CONCLUSIONS: The results of contemporaneous, nationwide assessment in the United States suggest that although pregnancy with Turner syndrome is uncommon this may represent a high-risk group, particularly for intrauterine fetal demise and periviable delivery. Establishing a society-based approach for preconception counseling and antenatal follow-up would be clinically compelling.

Pregnancy following assisted reproductive technology in morbidly obese patients: assessment of feto-maternal outcomes.

PURPOSE: To examine feto-maternal characteristics and outcomes of morbidly obese pregnant patients who conceived with assisted reproductive technology (ART). METHODS: This cross-sectional study queried the Healthcare Cost and Utilization Project's National Inpatient Sample. Study population was 48,365 patients with ART pregnancy from January 2012 to September 2015, including non-obesity (n = 45,125, 93.3%), class I-II obesity (n = 2445, 5.1%), and class III obesity (n = 795, 1.6%). Severe maternal morbidity at delivery per the Centers for Disease and Control Prevention definition was assessed with multivariable binary logistic regression model. RESULTS: Patients in the class III obesity group were more likely to have a hypertensive disorder (adjusted-odds ratio (aOR) 3.03, 95% confidence interval (CI) 2.61-3.52), diabetes mellitus (aOR 3.08, 95%CI 2.64-3.60), large for gestational age neonate (aOR 3.57, 95%CI 2.77-4.60), and intrauterine fetal demise (aOR 2.03, 95%CI 1.05-3.94) compared to those in the non-obesity group. Increased risks of hypertensive disease (aOR 1.35, 95%CI 1.14-1.60) and diabetes mellitus (aOR 1.39, 95%CI 1.17-1.66) in the class III obesity group remained robust even compared to the class I-II obesity group. After controlling for priori selected clinical, pregnancy, and delivery factors, patients with class III obesity were 70% more likely to have severe maternal morbidity at delivery compared to non-obese patients (8.2% vs 4.4%, aOR 1.70, 95%CI 1.30-2.22) whereas those with class I-II obesity were not (4.1% vs 4.4%, aOR 0.87, 95%CI 0.70-1.08). CONCLUSIONS: The results of this national-level analysis in the United States suggested that morbidly obese pregnant patients conceived with ART have increased risks of adverse fetal and maternal outcomes.

The unbearable ignorance of the composition of IVF culture media.

Culture media play an essential role in the success of IVF. Their composition has undergone major modifications over the 45 years since the birth of Louise Brown. Most IVF programmes now rely on commercially produced media, which they buy in small vials, guaranteed to be sterile and non-embryotoxic. Unfortunately, information about the components of the culture media and their concentrations is no longer available. Arguing that culture media recipes are proprietary, relevant commercial interests have stopped labelling their products with this vital information. Given the critical role that is played by culture media in the success of IVF, as well as the subsequent health of the children who are born after IVF, this information should not remain a 'company secret'. Clinicians and scientists working in IVF must insist that the labelling of culture media includes all of the constituents and their concentrations. Only in this way can we monitor the influence of culture media on IVF outcomes, innovate and continue to advance the field of IVF.

Contraception and sterilization selection at delivery among pregnant patients with malignancy.

INTRODUCTION: Since malignancy during pregnancy is uncommon, information regarding contraception selection or sterilization at delivery is limited. The objective of this study was to examine the type of long-acting reversible contraception or surgical sterilization procedure chosen by pregnant patients with malignancy at delivery. MATERIAL AND METHODS: This cross-sectional study queried the Healthcare Cost and Utilization Project's National Inpatient Sample in the USA. The study population was vaginal and cesarean deliveries in a hospital setting from January 2017 to December 2020. Pregnant patients with breast cancer (n = 1605), leukemia (n = 1190), lymphoma (n = 1120), thyroid cancer (n = 715), cervical cancer (n = 425) and melanoma (n = 400) were compared with 14 265 319 pregnant patients without malignancy. The main outcome measures were utilization of long-acting reversible contraception (subdermal implant or intrauterine device) and performance of permanent surgical sterilization (bilateral tubal ligation or bilateral salpingectomy) during the index hospital admission for delivery, assessed with a multinomial regression model controlling for clinical, pregnancy and delivery characteristics. RESULTS: When compared with pregnant patients without malignancy, pregnant patients with breast cancer were more likely to proceed with bilateral salpingectomy (adjusted odds ratio [aOR] 2.30) or intrauterine device (aOR 1.91); none received the subdermal implant. Pregnant patients with leukemia were more likely to choose a subdermal implant (aOR 2.22), whereas those with lymphoma were more likely to proceed with bilateral salpingectomy (aOR 1.93) and bilateral tubal ligation (aOR 1.76). Pregnant patients with thyroid cancer were more likely to proceed with bilateral tubal ligation (aOR 2.21) and none received the subdermal implant. No patients in the cervical cancer group selected long-acting reversible contraception, and they were more likely to proceed with bilateral salpingectomy (aOR 2.08). None in the melanoma group chose long-acting reversible contraception. Among pregnant patients aged <30, the odds of proceeding with bilateral salpingectomy were increased in patients with breast cancer (aOR 3.01), cervical cancer (aOR 2.26) or lymphoma (aOR 2.08). The odds of proceeding with bilateral tubal ligation in pregnant patients aged <30 with melanoma (aOR 5.36) was also increased. CONCLUSIONS: The results of this nationwide assessment in the United States suggest that among pregnant patients with malignancy, the preferred contraceptive option or method of sterilization at time of hospital delivery differs by malignancy type.

Association of HCG Level with Ultrasound Visualization of the Gestational Sac in Early Viable Pregnancies.

Our primary objective is to verify or refute a 2013 study by Connolly et al. which showed that in early pregnancy, a gestational sac was visualized 99% of the time on transvaginal ultrasound when the HCG level reached 3510 mIU/mL. Our secondary objective was to make clinical correlations by assessing the relationship between human chorionic gonadotropin (HCG) level in early pregnancy when a gestational sac is not seen and pregnancy outcomes of live birth, spontaneous abortion, and ectopic pregnancy. This retrospective study includes 144 pregnancies with an outcome of live birth, 87 pregnancies with an outcome of spontaneous abortion, and 59 ectopic pregnancies. Logistic regression is used to determine the probability of visualizing a gestational sac and/or yolk sac based on the HCG level. A gestational sac is predicted to be visualized 50% of the time at an HCG level of 979 mIU/mL, 90% at 2421 mIU/mL, and 99% of the time at 3994 mIU/mL. A yolk sac was predicted to be visualized 50% of the time at an HCG level of 4626 mIU/mL, 90% at 12,892 mIU/mL, and 99% at 39,454 mIU/mL. A total of 90% of ectopic pregnancies presented with an HCG level below 3994 mIU/mL. These results are in agreement with the study by Connolly et al. Since most early ectopic pregnancies had an HCG value below the discriminatory level for gestational sac visualization, other methods for the evaluation of pregnancy of unknown location such as repeat HCG values are clinically important.

Assessment of abnormal placentation in pregnancies conceived with assisted reproductive technology.

OBJECTIVE: To examine the association between assisted reproductive technology (ART) and abnormal placentation. METHODS: This is a retrospective cohort study querying the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample. The study population included 14, 970, 064 deliveries for national estimates from January 2012 to September 2015. The exposure was 48, 240 pregnancies after ART. The main outcome measure encompassed three abnormal placentation pathologies (placenta previa [PP], placenta accreta spectrum [PAS], and vasa previa [VP]). Propensity score matching was performed to assess the exposure-outcome association. RESULTS: Pregnancy after ART was more likely to have a diagnosis of PAS (2.8 vs 1.0 per 1000 deliveries; adjusted odds ratio [aOR], 2.06 [95% confidence interval (CI), 1.44-2.93]), PP (24.5 vs 8.6 per 1000; aOR, 2.98 [95% CI, 2.64-3.35]), and VP (2.3 vs <0.3 per 1000; aOR, 11.3 [95% CI, 5.86-21.8]) compared with pregnancy without ART. Similarly, pregnancy after ART was associated with an increased likelihood of having multiple types of abnormal placentation, including VP with PP (aOR, 15.4 [95% CI, 6.15-38.4]) and PAS with PP (aOR, 2.80 [95% CI, 1.32-5.92]) compared with non-ART pregnancy. CONCLUSIONS: This national-level analysis suggests that pregnancy after ART is associated with a significantly increased risk of abnormal placentation, including PAS, PP, and VP.

The association between uterine adenomyosis and adverse obstetric outcomes: A propensity score-matched analysis.

INTRODUCTION: This study examined obstetric outcomes in patients diagnosed with uterine adenomyosis. MATERIAL AND METHODS: This historical cohort study queried the Healthcare Cost and Utilization Project's National Inpatient Sample. The study population was all hospital deliveries in women aged 15-54 years between January 2016 and December 2019. The exposure was a diagnosis of uterine adenomyosis. The main outcome measures were obstetric characteristics, including placenta previa, placenta accreta spectrum, and placental abruption. Secondary outcomes were delivery complications including severe maternal morbidity. Analytic steps to assess these outcomes included (i) a 1-to-N propensity score matching to mitigate and balance prepregnancy confounders to assess obstetric characteristics, followed by (ii) an adjusting model with preselected pregnancy and delivery factors to assess maternal morbidity. Sensitivity analyses were also performed with restricted cohorts to account for prior uterine scar, uterine myoma, and extra-uterine endometriosis. RESULTS: After propensity score matching, 5430 patients with adenomyosis were compared to 21 720 patients without adenomyosis. Adenomyosis was associated with an increased odds of placenta accreta spectrum (adjusted-odds ratio [aOR] 3.07, 95% confidence interval [CI] 2.01-4.70), placenta abruption (aOR 3.21, 95% CI: 2.60-3.98), and placenta previa (aOR 5.08, 95% CI: 4.25-6.06). Delivery at <32 weeks of gestation (aOR 1.48, 95% CI: 1.24-1.77) and cesarean delivery (aOR 7.72, 95% CI: 7.04-8.47) were both increased in women with adenomyosis. Patients in the adenomyosis group were more likely to experience severe maternal morbidity at delivery compared to those in the nonadenomyosis group (aOR 1.86, 95% CI: 1.59-2.16). Results remained robust in the aforementioned several sensitivity analyses. CONCLUSIONS: This national-level analysis suggests that a diagnosis of uterine adenomyosis is associated with an increased risk of placental pathology (placenta accreta spectrum, placenta abruption, and placental previa) and adverse maternal outcomes at delivery.

Seasonal fluctuation of in vitro fertilization encounters in the United States.

PURPOSE: To examine patient and hospital characteristics related to seasonal fluctuation in in vitro fertilization (IVF). METHODS: This retrospective cohort study examined 33,077 oocyte retrievals identified in the National Ambulatory Surgery Sample. Exposure assignment was monthly IVF encounters: low-volume months (<25%ile), mid-volume months (≥25/<75%ile), and high-volume months (>75%ile). Main outcomes were patient and hospital characteristics related to the exposure groups, assessed with a multinomial regression model. RESULTS: The median IVF encounters were 977 per month, ranging from 657 to 1074 (absolute-difference 417). January, July, and December were the lowest-quartile volume months, ranging from 657 to 710 encounters per month (low-volume months). May, August, and November were the top-quartile volume months, ranging from 1049 to 1074 encounters per month (high-volume months). In a multivariable analysis, patients undergoing IVF in the low-volume months were younger and less likely to have infertility or comorbidities. Patients undergoing IVF in the high-volume months were more likely to have lower household income and receive IVF at urban teaching facilities. Northeastern residents were less likely to have IVF in the low-volume months but more likely to have IVF in the high-volume months. Sensitivity analyses showed that the lowest-to-highest variability in monthly IVF encounters was higher in Northeast region compared to other regions (320 vs 50-128); infertility patients compared to those without (317 vs 190); privately insured patients compared to self-pay (227 vs 156); and older patients compared to younger (234 vs 192). CONCLUSION: This study suggests substantial seasonal fluctuation in IVF oocyte retrieval in the USA based on patient and hospital factors.

Effects of parity on preterm delivery in twin gestations conceived with in vitro fertilization.

Objective: To determine the relationship between prior obstetrical history and gestational age at delivery in a twin pregnancy. Design: Retrospective cohort study using the United States Society for Assisted Reproductive Technology Clinic Outcomes Reporting System database. Setting: Clinic-based data. Patients: Patients undergoing in vitro fertilization (IVF) in the United States with live delivery of twins. Interventions: None. Main outcome measures: The main outcome measures are median gestational age at delivery and rate of preterm delivery (before 37 weeks). Results: The median gestational age at delivery of IVF-conceived twins was 36.3 (interquartile rate 34.4, 37.6) weeks for nulliparous women, 35.9 (34.0, 37.1) weeks for parous women with a prior preterm birth, and 36.7 (35.1, 37.7) weeks for parous women without a prior preterm birth. The rate of preterm delivery was 61% for nulliparous women, 70% for parous women with a prior preterm birth, and 55% for parous women without a prior preterm birth. Conclusions: Parous women without a history of preterm delivery had lower rates of preterm delivery in a subsequent twin pregnancy than nulliparous women. Nulliparous women had lower rates of preterm delivery compared with parous women with a history of preterm delivery.

The potential role of GLP-1 receptor agonist targeting in fertility-sparing treatment in obese patients with endometrial malignant pathology: a call for research.

INTRODUCTION: Most patients diagnosed with endometrial hyperplasia or cancer are obese. Obesity, along with polycystic ovarian syndrome (PCOS) and type-2 diabetes mellitus (T2DM), may act synergistically to increase risk of malignant endometrial pathology. Incidence of malignant endometrial pathology is increasing, particularly in reproductive aged women. In patients who desire future fertility, the levonorgestrel intrauterine device (LNG-IUD) is often utilized. If the first-line progestin therapy fails, there is not an effective second-line adjunct option. Moreover, pregnancy rates following fertility-sparing treatment are lower-than-expected in these patients. AREAS COVERED: This clinical opinion provides a summary of recent studies exploring risk factors for the development of malignant endometrial pathology including obesity, PCOS, and T2DM. Studies assessing efficacy of fertility-sparing treatment of malignant endometrial pathology are reviewed, and a potential new adjunct treatment approach to LNG-IUD is explored. EXPERT OPINION: There is an unmet-need for a personalized treatment approach in cases of first-line progestin treatment failure. Glucagon-like peptide 1 receptor agonists are a class of anti-diabetic agents, but may have a role in fertility-sparing treatment of obese patients with malignant endometrial pathology by reducing weight, decreasing inflammation, and decreasing insulin resistance; these changes may also improve chances of subsequent pregnancy. This hypothesis warrants further exploration.

Uptake of postplacental intrauterine device placement at cesarean delivery.

BACKGROUND: Several studies have investigated the effectiveness of intrauterine device placement at cesarean delivery as a contraceptive method. However, national-level use and outcomes of a postplacental intrauterine device at cesarean delivery are currently understudied in the United States. OBJECTIVE: This study aimed to examine the trends, characteristics, and outcomes of patients who received a postplacental intrauterine device at cesarean delivery. STUDY DESIGN: This retrospective cohort study used the National Inpatient Sample. The study cohort included patients who underwent cesarean delivery from October 2015 to December 2018. The exclusion criteria included hemorrhage, chorioamnionitis, uterine anomaly, hysterectomy, and permanent surgical sterilization. Eligible cases were grouped on the basis of the use of a postplacental intrauterine device at cesarean delivery. The primary outcome measures were temporal trends and characteristics associated with the use of a postplacental intrauterine device at cesarean delivery, assessed using the generalized estimating equation model in multivariable analysis. The secondary outcome measure was perioperative morbidity (leukocytosis, endometritis, myometritis, and sepsis). Propensity score matching was used to balance the baseline characteristics. RESULTS: Among 2,983,978 patients who met the inclusion criteria, 10,145 patients (0.3%) received a postplacental intrauterine device at cesarean delivery. The use of a postplacental intrauterine device increased from 0.1% in the fourth quarter of 2015 to 0.6% in the fourth quarter of 2018 (P<.001). In a multivariable analysis, the use of a postplacental intrauterine device increased by 14% every quarter-year (adjusted odds ratio, 1.14; 95% confidence interval, 1.13-1.15). In addition, (1) patient characteristics of young age, non-White race, obesity, tobacco use, lowest quartile median household income, and insured with Medicaid; (2) hospital characteristics of large bed capacity and urban teaching setting in Northeast region; and (3) pregnancy characteristics of early gestational age at cesarean delivery, hypertensive disease, previous cesarean delivery, multifetal pregnancy, grand multiparity, placenta previa, and nonelective cesarean delivery represented the independent characteristics associated with the use of a postplacental intrauterine device (all P<.05). A regression tree model identified 35 discrete patterns of the use of a postplacental intrauterine device based on 8 factors (time, race or ethnicity, primary expected payer, obesity, hospital bed capacity, hospital teaching status, hospital region, and previous cesarean delivery). There were 9 patterns, representing 8.8% of the study population, exhibiting a use rate of ≥1.0%, whereas there were 7 patterns, representing 16.0% of the study population, exhibiting no use of a postplacental intrauterine device (absolute rate difference from the highest group to the lowest group, 4.7%). In a propensity score-matched model, postplacental intrauterine device placement at cesarean delivery was not associated with increased risk of measured morbidity (any, 1.8% vs 1.7%; odds ratio, 1.06; 95% confidence interval, 0.66-1.69; P=.812), including postpartum endometritis (1.2% vs 1.0%; odds ratio, 1.19; 95% confidence interval, 0.67-2.14; P=.554). CONCLUSION: The use of a postplacental intrauterine device at cesarean delivery increased significantly in recent years in the United States.

More follicle-stimulating hormone may not improve outcomes, but can it be counterproductive?

Many studies have sought to explore the impact of high-dose gonadotropin on stimulation outcomes based on a hypothesis that higher doses of follicle-stimulating hormone may harm the quantity or quality of oocytes and, therefore, be counterproductive. Herein, we describe the results of a narrative review aimed at elucidating any harm associated with "excess" follicle-stimulating hormone dosing in poor-to-moderate responders. Additionally, we sought to describe the outcomes associated with mild ovarian stimulation, with an eye toward determining whether this approach is superior. We concluded that there is no apparent harm to higher-dose gonadotropin stimulation for poor-to-moderate responders. Simultaneously, we did not find compelling data to suggest that mild stimulation is superior. Finally, we close by presenting data that suggest that more gonadotropin may be beneficial in specific clinical scenarios.

Consistency of endometrial receptivity array and histologic dating of spatially distinct endometrial samplings: a prospective, blinded study.

Objective: To compare the consistency of endometrial receptivity array (ERA) and histologic dating among 3 spatially distinct endometrial samples obtained during a cycle of exogenous estrogen and progesterone. Design: Prospective blinded study. Setting: University practice. Patients: Twelve patients undergoing a mock frozen embryo transfer cycle. Intervention: Endometrial biopsy was performed in a manner that provided a spatially organized endometrial specimen, corresponding to the fundus, middle, and lower segment. Each of these 3 sections was further divided into immediately adjacent specimens for ERA and histology. Main Outcome Measure: Consistency of the ERA and histology results among fundal, mid, and lower endometrial biopsy specimens. Results: The ERA showed variability in outcome among different patients but dated all specimens originating from the same patient identically. Histologic dating showed variability between patients as well as between different locations within the uterus. When comparing average dating results for each patient, we saw a positive correlation between histologic and ERA dating (Spearman Rho = 0.45); however, this did not reach statistical significance. The ERA results from upper, mid, and lower uterine biopsy specimens were identical for each autologous biopsy, whereas histologic dating showed variability with an average standard deviation of 0.71 days. Conclusions: The increased heterogeneity of histologic dating is likely to be attributed to the subjectivity of the test. Furthermore, we did not observe a consistent lag or advancement in histologic or ERA dating between the fundal or lower uterine biopsies. Overall, clinicians should be reassured that endometrial tissue will return consistent ERA results independent of the location within the uterus in which it was obtained.